The objective of this project is to use biochemical morphological and cell fractionation techniques to analyze structurally and functionally the integrative mechanism by which hormones regulate fat cell metabolism. Major focus has been and will be on: 1. the subcellular localization of insulin and epinephrine receptors and degradative systems both biochemically and electron microscopically; 2. the role and subcellular distribution of various enzymes in the mechanism of insulin and epinephrine action; 3. the subcellular distribution, binding and transport of calcium and its relationship to insulin and epinephrine action. BIBLIOGRAPHIC REFENCES: Lemay, A. and Jarett, L.: Pitfalls in the use of lead nitrate for the histochemical demonstration of adenylate cyclase activity. J. Cell Biol. 65: 39-50, 1975. Hammond, J. and Jarett, L.: The characterization and subcellular distribution of insulin degradative activity of adipocytes. Diabetes 24:1011-1019, 1975.